摘要
为了探明新疆X湖高寒、高海拔采矿活动对该区环境中重金属的影响,采集不同点位土壤、水体和底泥沉积物进行系统评价。结果表明:该矿区土壤重金属平均含量均高于新疆土壤背景值,重金属在土壤中出现累积,采矿活动对土壤重金属的污染主要集中于As、Cd、Cu、Pb、Zn元素;总体上,随着海拔高度的升高,As和Cd浓度逐渐降低,而其他元素大致呈现逐渐升高的规律,各重金属元素在尾矿区出现明显累积。结合土壤重金属的正态分布、主成分分析/绝对主成分分数(PCA/APCS)受体模型、相关性分析和富集因子(EFs)分析可知,As、Cd和Cu的富集主要来源于采矿活动中产生的污染物,Pb和Zn的累积主要来源于尾矿的元素溶出和施工车辆尾气的排放污染。评价结果表明区域水体水质状况良好,未出现重金属元素超标情况;As、Pb、Cd未在沉积物中富集,而Zn、Cu、Ni、Cr均出现富集。沉积物重金属的潜在生态危害指数和地累积指数评价结果表明,尾矿区至采矿区部分点位为中度污染,且沉积物中重金属污染程度高于土壤。进一步开展高寒、高海拔矿区周边重金属元素的迁移转化规律及环境阈值研究,以及寻找适宜的生态恢复措施具有重要意义。
To evaluate the impact of mining activity on heavy metals in a high-altitude freezing and thawing area in Xinjiang,soil,water and sediment at different sampling points were systematically evaluated.The results show that the average heavy-metal contents in the mining area were higher than that of the background of Xinjiang area and showed an accumulation trend in the soil.As,Cd,Cu,Pb,and Zn are the main heavy-metal pollutants caused by the mining activities.In general,the concentration of As and Cd gradually decreased as the elevation increased,while other elements generally showed gradual increasing trends;heavy metals were also accumulated in the tailings area.Results show that the enrichment of As,Cd,and Cu was mainly derived from mining activities,while the accumulation of Pb and Zn was mainly affected by the element dissolution of the tailings and emissions from the construction vehicles.The surface water quality in the assessment area was adequate and no heavy metal elements exceeded the standard.As,Pb and Cd were not accumulated in the sediment,but Zn,Cu,Ni and Cr were enriched.The Potential Ecological Risk Index(RI)and the Ground Accumulation Index analysis of the heavy-metal sediment indicate that some points of the tailing area of the mining area were moderately polluted and the heavy-metal contamination in the sediments was generally higher than that in the soil.Furthering the study on the migration and transformation of heavy-metal elements and environmental threshold in high-altitude and freezing mining areas can be significant in finding suitable ecological restoration measures.
作者
袁程昱
李发永
袁自强
胡雪菲
尤永军
王闪
李国玉
YUAN Cheng-yu;LI Fa-yong;YUAN Zi-qiang;HU Xue-fei;YOU Yong-jun;WANG Shan;LI Guo-yu(College of Water Resources and Architectural Engineering,Tarim University,Alaer 843300,China;Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China)
出处
《生态与农村环境学报》
CAS
CSCD
北大核心
2020年第5期679-688,共10页
Journal of Ecology and Rural Environment
基金
国家自然科学基金新疆联合基金重点项目(U1703244)。
关键词
重金属
海拔
土壤
水体
沉积物
heavy metal
altitude
soil
waterbody
sediment
